diff --git a/lib/day4/day4.ex b/lib/day4/day4.ex
index 072fc3a..c439ce3 100644
--- a/lib/day4/day4.ex
+++ b/lib/day4/day4.ex
@@ -1,5 +1,4 @@
 defmodule Day4 do
-
   defmodule Timestamp do
     defstruct [:year, :month, :day, :hour, :minute]
 
@@ -9,7 +8,7 @@ defmodule Day4 do
         month: m |> String.to_integer(),
         day: d |> String.to_integer(),
         hour: h |> String.to_integer(),
-        minute: min |> String.to_integer
+        minute: min |> String.to_integer()
       }
     end
 
@@ -17,10 +16,11 @@ defmodule Day4 do
       first.minute..second.minute
     end
   end
-  
+
   def parse_event(line) do
     res = Regex.run(~r/\[(\d+)-(\d+)-(\d+) (\d+):(\d+)\] (.+)/, line)
     [_line, y, m, d, h, min, event | _tail] = res
+
     {
       Timestamp.create(y, m, d, h, min),
       event
@@ -53,10 +53,12 @@ defmodule Day4 do
         _id -> {:cont, Enum.reverse(acc), [event]}
       end
     end
+
     after_fun = fn
       [] -> {:cont, []}
       acc -> {:cont, Enum.reverse(acc), acc}
     end
+
     events
     |> Enum.chunk_while([], chunk_fun, after_fun)
     |> Enum.reject(fn
@@ -65,11 +67,14 @@ defmodule Day4 do
     end)
     |> Enum.reduce(%{}, fn [begin_shift | events], acc ->
       guard_id = parse_guard(begin_shift)
-      ranges = events
-      |> Enum.chunk_every(2)
-      |> Enum.map(fn [{sleep, _}, {wake, _} | []] ->
-        Timestamp.range(sleep, wake)
-      end)
+
+      ranges =
+        events
+        |> Enum.chunk_every(2)
+        |> Enum.map(fn [{sleep, _}, {wake, _} | []] ->
+          Timestamp.range(sleep, wake)
+        end)
+
       Map.update(acc, guard_id, ranges, &(&1 ++ ranges))
     end)
     |> Enum.reject(fn
@@ -81,38 +86,48 @@ defmodule Day4 do
   def get_max_sleep_time(guards) do
     guards
     |> Enum.map(fn {id, times} ->
-      total = times
-      |> Enum.map(fn a..b -> b - a end)
-      |> Enum.sum()
-      {minute, _count} = times
-      |> Enum.flat_map(&Enum.to_list/1)
-      |> Enum.reduce(%{}, fn minute, acc ->
-        Map.update(acc, minute, 1, &(&1 + 1))
-      end)
-      |> Enum.max_by(fn {_minute, count} -> count end)
+      total =
+        times
+        |> Enum.map(fn a..b -> b - a end)
+        |> Enum.sum()
+
+      {minute, _count} =
+        times
+        |> Enum.flat_map(&Enum.to_list/1)
+        |> Enum.reduce(%{}, fn minute, acc ->
+          Map.update(acc, minute, 1, &(&1 + 1))
+        end)
+        |> Enum.max_by(fn {_minute, count} -> count end)
+
       {id, total, minute}
     end)
     |> Enum.max_by(fn {_id, total, _minute} -> total end)
   end
 
   def range_containing(ranges) do
-    first = Enum.reduce(ranges, Enum.at(ranges, 0).first, fn first.._, acc ->
-      min(first, acc)
-    end)
-    last = Enum.reduce(ranges, Enum.at(ranges, 0).last, fn _..last, acc ->
-      max(last, acc)
-    end)
+    first =
+      Enum.reduce(ranges, Enum.at(ranges, 0).first, fn first.._, acc ->
+        min(first, acc)
+      end)
+
+    last =
+      Enum.reduce(ranges, Enum.at(ranges, 0).last, fn _..last, acc ->
+        max(last, acc)
+      end)
+
     first..last
   end
 
   def get_most_frequent_sleep_time(guards) do
     guards
     |> Enum.map(fn {id, times} ->
-      {minute, count} = range_containing(times)
-      |> Enum.map(fn minute ->
-        {minute, Enum.count(times, fn range -> minute in range end)}
-      end)
-      |> Enum.max_by(fn {_minute, count} -> count end)
+      {minute, count} =
+        range_containing(times)
+        |> Enum.map(fn minute ->
+          {minute, Enum.count(times, fn range -> minute in range end)}
+        end)
+        |> Enum.max_by(fn {_minute, count} -> count end)
+
       {id, minute, count}
     end)
     |> Enum.max_by(fn {_id, _minute, count} -> count end)
@@ -124,21 +139,24 @@ defmodule Day4 do
   end
 
   def part1() do
-    {id, _total, minute} = parse_input()
-    |> parse_events()
-    |> sort_events()
-    |> get_sleep_times()
-    |> get_max_sleep_time()
+    {id, _total, minute} =
+      parse_input()
+      |> parse_events()
+      |> sort_events()
+      |> get_sleep_times()
+      |> get_max_sleep_time()
+
     String.to_integer(id) * minute
   end
 
   def part2() do
-    {id, minute, _count} = parse_input()
-    |> parse_events()
-    |> sort_events()
-    |> get_sleep_times()
-    |> get_most_frequent_sleep_time()
+    {id, minute, _count} =
+      parse_input()
+      |> parse_events()
+      |> sort_events()
+      |> get_sleep_times()
+      |> get_most_frequent_sleep_time()
+
     String.to_integer(id) * minute
   end
-
-end
\ No newline at end of file
+end
diff --git a/lib/day5/day5.ex b/lib/day5/day5.ex
index 124c6c9..7af3082 100644
--- a/lib/day5/day5.ex
+++ b/lib/day5/day5.ex
@@ -1,5 +1,4 @@
 defmodule Day5 do
-  
   @doc """
   Compares two codepoints for opposite case.
 
@@ -18,6 +17,7 @@ defmodule Day5 do
         else
           [c | s]
         end
+
       c, [] ->
         [c]
     end)
@@ -76,6 +76,7 @@ defmodule Day5 do
       s = <<c::utf8>>
       str = String.replace(input, s, "")
       str = String.replace(str, String.upcase(s), "")
+
       input
       |> String.replace(s, "")
       |> String.replace(String.upcase(s), "")
@@ -87,7 +88,7 @@ defmodule Day5 do
   end
 
   def parse_input() do
-    File.read!("lib/day5/input.txt")    
+    File.read!("lib/day5/input.txt")
   end
 
   def part1() do
@@ -101,5 +102,4 @@ defmodule Day5 do
     parse_input()
     |> min_length()
   end
-
-end
\ No newline at end of file
+end
diff --git a/lib/day6/day6.ex b/lib/day6/day6.ex
index 6fb0e08..d0fe9a3 100644
--- a/lib/day6/day6.ex
+++ b/lib/day6/day6.ex
@@ -1,5 +1,4 @@
 defmodule Day6 do
-  
   @doc """
   Parses a node from a string.
 
@@ -11,6 +10,7 @@ defmodule Day6 do
   """
   def parse_node(s) do
     [x, y] = String.split(s, ", ")
+
     {
       x |> String.to_integer(),
       y |> String.to_integer()
@@ -39,7 +39,7 @@ defmodule Day6 do
       nil
   """
   def nearest_node(point, all) do
-    nearest = 
+    nearest =
       all
       |> Enum.map(fn other -> {other, distance(point, other)} end)
 
@@ -58,9 +58,11 @@ defmodule Day6 do
         0..grid_size
         |> Enum.reduce(acc, fn x, {areas, infinite_area_nodes} ->
           pt = {x, y}
+
           case nearest_node(pt, nodes) do
             nil ->
               {areas, infinite_area_nodes}
+
             nearest ->
               if x == 0 or y == 0 or x == grid_size or y == grid_size do
                 {
@@ -102,9 +104,11 @@ defmodule Day6 do
       0..grid_size
       |> Enum.reduce(acc, fn x, acc ->
         pt = {x, y}
+
         cond do
           total_distances(pt, nodes) < max_dist ->
             [pt | acc]
+
           true ->
             acc
         end
@@ -128,5 +132,4 @@ defmodule Day6 do
     |> region_near_most()
     |> Enum.count()
   end
-
-end
\ No newline at end of file
+end
diff --git a/test/day4_test.exs b/test/day4_test.exs
index 74e0e60..db8f2ad 100644
--- a/test/day4_test.exs
+++ b/test/day4_test.exs
@@ -4,11 +4,15 @@ defmodule Day4Test do
   alias Day4.Timestamp
 
   test "parse event" do
-    assert Day4.parse_event("[1518-11-01 00:00] Guard #10 begins shift") == {%Timestamp{year: 1518, month: 11, day: 01, hour: 0, minute: 0}, "Guard #10 begins shift"}
+    assert Day4.parse_event("[1518-11-01 00:00] Guard #10 begins shift") ==
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 0, minute: 0},
+              "Guard #10 begins shift"}
   end
 
   test "parse guard" do
-    event = {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00}, "Guard #10 begins shift"}
+    event =
+      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00}, "Guard #10 begins shift"}
+
     assert Day4.parse_guard(event) == "10"
   end
 
@@ -17,17 +21,19 @@ defmodule Day4Test do
       {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 05}, "falls asleep"},
       {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 55}, "wakes up"},
       {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 25}, "wakes up"},
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00}, "Guard #10 begins shift"},
+      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00},
+       "Guard #10 begins shift"},
       {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 30}, "falls asleep"}
     ]
 
     assert Day4.sort_events(events) == [
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00}, "Guard #10 begins shift"},
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 05}, "falls asleep"},
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 25}, "wakes up"},
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 30}, "falls asleep"},
-      {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 55}, "wakes up"}
-    ]
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 00},
+              "Guard #10 begins shift"},
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 05}, "falls asleep"},
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 25}, "wakes up"},
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 30}, "falls asleep"},
+             {%Timestamp{year: 1518, month: 11, day: 01, hour: 00, minute: 55}, "wakes up"}
+           ]
   end
 
   test "get sleep times" do
@@ -52,9 +58,9 @@ defmodule Day4Test do
     ]
 
     assert Day4.get_sleep_times(events) == [
-      {"10", [5..25, 30..55, 24..29]},
-      {"99", [40..50, 36..46, 45..55]}
-    ]
+             {"10", [5..25, 30..55, 24..29]},
+             {"99", [40..50, 36..46, 45..55]}
+           ]
   end
 
   test "get max sleep time" do
@@ -79,5 +85,4 @@ defmodule Day4Test do
 
     assert Day4.get_most_frequent_sleep_time(guards) == {"99", 45, 3}
   end
-
-end
\ No newline at end of file
+end
diff --git a/test/day5/day5_test.exs b/test/day5/day5_test.exs
index 4237006..336f317 100644
--- a/test/day5/day5_test.exs
+++ b/test/day5/day5_test.exs
@@ -1,4 +1,4 @@
 defmodule Day5Test do
   use ExUnit.Case
   doctest Day5
-end
\ No newline at end of file
+end
diff --git a/test/day6_test.exs b/test/day6_test.exs
index 51a7be2..3ea86bb 100644
--- a/test/day6_test.exs
+++ b/test/day6_test.exs
@@ -1,4 +1,4 @@
 defmodule Day6Test do
   use ExUnit.Case
   doctest Day6
-end
\ No newline at end of file
+end